In electron devices such as semiconductor devices, it is now becoming possible, as a result of progress of exposure technology, to produce ultrafine electron devices such as ultrafine semiconductor devices with a pattern width of several ten nanometers or less.
On the other hand, when attempt is made to advance this trend of miniaturization furthermore for mass-production of further miniaturized semiconductor devices, huge investment becomes necessary for steppers, reticles, and the like, and there arises the problem of sharp increase of production cost of the electron devices.